Tube holder and lighting system



Dec. 2', 1952 E. G. GODDARD 2,620,372

TUBE HOLDER AND LIGHTING SYSTEM Filed Oct. 11, 1948 5 Sheets-Sheet 1 \NSUL.ATION Dec. 2, 1952 E. e. GODDARD 2,520,372

TUBE HOLDER AND LIGHTING SYSTEM Filed Oct. l1, 1948 5 Sheets-Sheet 2 JX Z5 f J zj Z7 22 4 28 v Z9 l ||||||y HMI.7 l o G o Z6 o 0 O e f4 (Wil. f

M14/legs Dec. 2, 1952 E. G. GODDARD 2,620,372

TUBE HOLDER AND LIGHTING SYSTEM Filed Oct. 1l, 1948 3 Sheets-Sheet 3 \N5ULATION shown in Fig. 2, the cover Patented Dec. 2, T952 UNITED STATES PATENT OFFICE` 2,620,372 TUBE HoLDEa AND LIGHTING SYSTEM Edwin G. Goddard, Lombard, n1. Application October 11, 1948, Serial No. 53,771

Claims.

This invention relates to an improved tube holder for fluorescent lamps or the like, and to an improved safety lighting system embodying such tube holder.

This application is an improvement on the invention of my application Serial No. 631,679 filed November 29, 1945, now abandoned.

That application relates to a safety lighting system which is relatively foolproof. Morek particularly, means are provided for automatically breaking the primary circuit ofthe energizing transformer when any one of several tubes is removed from the system. Thus all of the secondary circuits go dead and there is no danger of shock to the operator. Such a system is particularly well adapted for use in connection with gaseous induction tubes of the type which require a starting voltage several times in excess of the operating voltage. For instance, the so-called quick start tube in use today requires a starting voltage of from 450 to 1,000 volts which may be considered dangerous from the shock standpoint to the average user. A Y It is an object of my invention to provide a lighting system in which the terminals of the tubes are themselves utilized as certain ones of a plurality of conducting elements necessary to establish a series circuit with the primary of the transformer so that the removal of any one tube will automatically deenergize the transformer.

It is a further object of the present invention to provide a tube holder in which the tube terminal contacting elements themselves, in combination with the tube terminals, constitute all of the conductors necessary to establish the series circuit for the primary of the transformer. Thus, separate circuit breaking means are eliminated, resulting in a tube holder of more simple design than that disclosed in my prior application, and one which can be manufactured at less cost.

Other objects, features and advantages will become apparent as this description proceeds.

With respect to the drawings which illustrate a preferred embodiment of my invention and in which like reference numerals represent like parts:

Fig. 1 is a perspective view showing the relationship of the tubes and tube holders;

Fig. 2 is an' elevation of a tube holder embodying my invention, the cover being removed;

Fig. 3 is an end elevation of the tube holder being shown rin dotted lines; Fig. 4 is an enlarged detailed sectional view taken along line 4-4 of Fig. 2;

Fig. 5 is a bottom plan view of the tube holder and tube assembly, portions being broken away;

Fig. 6 is a wiring diagram of the lighting system embodying my invention;

Fig. 7 is a diagram showing a modification; and

Figs. 8, 9, 10 and 11 are views showing a further modification.

The reference numeral I0 designates generally a plurality of fluorescent tubes which are mounted in side by side relationship in tube holders II and I2. The tubes are individually designated by the reference numerals Illa, Illb, I0c, and IIJd, respectively.

The tube holder II comprises a base I3 and a cover I4 as shown in Fig. 3, the cover being shown in dotted lines. The base I3 is made from sheet metal having turned up edges which are adapted to engage the edges of the cover I4, which is generally box-shaped. One of the side walls of the cover is provided with a series of apertures 20 throughv which the tubes I0 may be inserted. y l

A plate I'I of suitable insulating material depends vertically from the base I3 and is secured thereto by means of brackets I8. IThe plate is provided with a series of apertures I2 which are in alignment with the apertures 20 but which may be considerably smaller since they receive only the tube terminals 29 which are of considerably smaller diameter than the tubes themselves.

A plurality of resilient contact strips are secured to the rear surface of the plate Il, these strips being designated by the reference numerals 2l to 25 inclusive.

The strips are arranged as shown in Fig. 2 so that the` end portions of two diierent strips overlie each one of the apertures I9. The strips 22, 23 and 24 can be termed double strips since they are secured to the plate Il at their midpoint by means of rivets 20, the two free ends of these tube strips overlying portions of adjacent apertures. In other words, the double strips serve to provide a connection between the tube terminals which are received in adjacent apertures. The strips 2| and 25 which overlie a portion of the end apertures can be termed single strips since they have only one free end, the other end being anchored to the plate Il by means of rivets 26. A terminal 2l' is secured to strip 2I in electrical conducting relationship and a terminal 28 is secured to strip 25 in electrical conducting relationship. The rivets 2B which anchor the strips 2I and 25 to the plate I1 also pass through the terminals` 2l and 28, as shown in Fig. 4. The terminals 2l and 28 include a screw by means of which conductors may be secured thereto.

As shown in Fig. the tube terminals 29 are in the form of pins which are adapted to project into the apertures I9 and engage both of the resilient strips which overlie portions of each aperture. When the parts are in operative position as shown in Fig. 5 the resilient strips will. be displaced.backwardlyto acertain extent, although theshowing in Fig. 5 may be exaggerated in this respect for purposes of illustration. Thus, the tube terminals 29 serve as bridging members which bridge the gaps betweenthe endportions of adjacent resilient strips and serve to connect all of said resilient strips in seriescireuit with each other. When all of thetubes are` in operative position, a circuit is established between the terminals 27 and 28.

The tube holder l2 is provided with an insulating.n plate.- Si]j which. is.v suitably supported from the.-base. l5., asr shown in .Fig-5. VOn the.l base 5i!v aremounted fa plurality of coiled contact springs 3B which are adapted to beextendedrear.- w-ardly when engagedby the terminal. of a... tube to form a socket for resiliently supporting Vthe tube. The contact springs; 3Q. also engage. the tube terminals 29 in electrically conductingcrelationship, and eachv one of` the Contact springs i'sprovided witha terminal 3l to which a. conductor may-besecured. In4 Eig.. 5, tubeA i3d is broken off for illustrative purposes, showing. its respective spring` 3i] incollapsed position and exposing the terminal 3 I. The sidewall othe cover l5l is provided with a series of apertures32 with which thevcontact springs Sil. are aligned..

Irropera-tion, one end of a tubeill is iirstinsertedwintofthe apertures of the tube holder I2 and is caused toengage-the spring S@ and distend/thelsame'sufeiently so'th'at the other-end of the tube will'clear the tube holder l I. Then the'tube'terminal misguided through the corresponding aperture 20 in the tube holder Hand into fthe aperture H at which point it. engages therpair of the resilient contact stripsI andbridges the. gap between them. During this time'thetension1 onthe `contact springs 3Q is somewhat relaXed; asY th'e'opposite: end of the tube is moved intothe h'older H. The contact springs V3l) should bedisposedsuiciently close to the apertured-:wall of the tube holder l2 as' to permit distension ofthe spring so as ltoenable the` opposite end` of, the tubeV to 'clear the holder H. The series circuit 'between terminals 21 and-25 Ywill remain broken until the last tube'is in place, with the. resultr that; thewhole; system isr dead until the; nal. step istaken.

The manner in rwhich Ythej parts; are connected int'o. circuit withsuitable energizing means is shown di'agrammatically "in Fig; 6.

The .reference numerals 35 and. 35; designate power lines connected with a suitable source of power; The referencenumeral's 3-1' and, 38 designate the primary Yand v.secondary coils, respectively, ofA onev autotransformer and the reference numerals 3B and di) designate the primary and secondary coils, respectively, of another auto- 't'ransformen The power liney 35 isf-:connected to taps between the primary and secondaryl coils of" each of the. two autotransformers, by leads 41 and 42; Leads l3- and connect the other side of' the primary coils 'Ii-'i' andv 32 with terminal ZIof theftube holder'l l. Terminal Si' of the tube holder 28 is; connected to the power line 3B.

litA will' .be seen. that. the "circuit through the primariesB] and 39= will be opened by .the removal of a single tube lil, thereby deenergizing the primary circuit. Tubes lila and iib are conn nected in parallel with the secondary circuit of one autotransiormer which includes coils 3l, 38 and suitable inductances dla and Mb. The condenser (lb is provided for the tube Gb to reduce stroboscopic eiect. The secondary circuit for tubes lilo and Mld includes coils 3d and and inductanccs ficand sld. A. condenser @Scl is also provided in series with tube idd'.

In this arrangement of the parts it will be seen that not only is the secondary circuit for a particular tube broken when that tube is removed, but the primary circuit for both autotransformers is also broken, thereby deenergizing. all of the tubes. This is because the tube terminals-csserve to bridge the gaps between adjacent resilient contact strips, and as soon as one tube is removed, the series contact between the elements willbe broken.

lt will be understood that aA separate` con.- ductoris provided for each` of the coiled contact springs Sil in holder 12.

For thepurposes of this invention, ,it is irnmaterial whether. only oneA ofthe secondary cir..n cuits of each transformeris provided with a condenser or whether both vsecondary circuits are.. Furthermore, the inductances may be eliminated provided that sumcient impedance is present in the .combination transformer and Acondenser means. Also, it will be understood Vthat instead of the autotransormers. shown. in Fig. 6, insulatedtransformers may be used, providing vthat a portion of. the secondary circuit also comprises a portion of the. primary. circuit, the common portion including the resilient contact members and tube terminals referredto. above.

The operation or"` the circuit asawhole, and a Vdescription of. the. steps involved in inserting andv removing the tubes has been given above in connectionwith the descriptionl of 'the various elements. It will be seen that theglighting system above described is practically foolproof.' Eurthermore, the .covers of.. the. holders do notfneed to be removed to permit. the insertionv or removal of a tube..

It is obvious that -tubes .havingother types of terminals may be .utilized in the tube holder and system above described. The size of. the apertures is may be varied toY receive the ierrule type tube terminal shown in my earlier application. Also, the present invention may be applied to the two pin type of terminal either with or without a shorted filament,v one of the. terminal engaging members engagingv one .ofv the vpins .and the other of the members engaging. ythe other of the pins. Thus, the .two pins of the terminal serveto bridge the gap between the two terminal engaging members.

Such an arrangement is shown in Eig. 7. in which plate Il is provided with a= series of pairs of apertures vl and 52, respectively,vfor receiving pins 53 and 5t of tube terminals 55; In this arrangement, a' double resilient strip '56v is provided for engaging pins 53. and V54 of` adjacent tubes. Resilient contact strips 57 and 58 can either be single strips provided with suitable terminals or can. represent portionsof double strips, they opposite ends of which Yare-engaged by pins of adjacent tube terminals in much the same man-ner as described inconnection with' the preceding gures.

Furthermore, instead of providing tubecontacting members `ini the form. of resilient contact strips which are. displacedl backwardlyr when engaged by a tube terminal, contact members maybe provided which will be displaced in a lateralv direction when engaged by the tube terminals, the tube terminal thus serving to bridge the gap. between the two contact members as well as being connected into its respective secondary circuits.Such an arrangement is shownin Figs. 8,v 9, and 11 which represent a'modied form of tubeY holder. Two insulating members 60 Land 6l are secured to each other in perpendicular. relationship, the insulating member 60 being disk-shaped and being provided with an aperture 62. The member 60 is provided with an aperture 62. The member 6| is provided with a cut-away portion 63 to permit the insertion of a tube terminal through aperture 62. Resilient contact strips 64 and 65 having suitable terminals 66 and 61, respectively, are suitably secured to the insulating member 6| in such a manner that they will engage the opposite sides of a tube terminal and be displaced laterally by the tube terminal as it is inserted in aperture 62. Thus, the gap between the contact members 64 and 65 is bridged by the tube terminal. Any number of such tube holders may be mounted in a suitable housing, with the terminals of adjacent holders connected to each other so as to provide a series circuit which will be broken by the removal of any one tube.

It will be understood that the term tube as used herein covers the term lamp Although preferred embodiments of my in vention have been shown and described herein, it will be understood that various modifications and .changes may be made without departing from the spirit of this invention. The foregoing description and the drawings are illustrative only and the invention is to be limited only by the appended claims.

I claim:

1. A tube holder for supporting one end of a plurality of lamp tubes in side by side relationship comprising a tube supporting member formed of insulating material and having a series of apertures disposed in side by side relationship for receiving the terminals of said tubes, a plurality of pairs of flat leaf springs disposed in a plane parallel to the rear surface of said tube supporting member, means securing a portion of each leaf spring to the rear surface of said tube supporting member so that the free end portions of each pair of leaf springs will overlie each aperture of said series whereby each tube terminal will be engaged by two of said leaf springs, said free end portions being spaced from each other, the free end portion of one leaf spring of each pair being in direct electrical connection with the free end portion of one leaf spring of an adjacent pair, whereby a series connection will be established through the spaced end portions of said leaf springs and through the tube terminals when a tube terminal is received in each of said apertures.

2. A tube holder for supporting one end of a plurality of lamp tubes in side by side relationship comprising a plate formed of insulating material and having a series of apertures disposed in side by side relationship for receiving the terminals of said tubes, a plurality of substantially flat resilient contact strips spaced from each other and disposed in a plane parallel to the plane of said plate and anchored to said plate and arranged so that each aperture will be partially covered by the free end portions of two of said contact strips, the two free end portions overlying an aperture being spaced from each other whereby each tube terminal will be engaged by two of said resilient contact strips, the free end portion of one of the two contact strips overlying each opening being in direct electrical connection with the free end portion of one of the contact strips overlying an adjacent opening whereby a series connection will be established through the spaced free end portions of said contact strips and through the tube terminals when a tube terminal is received in each of said apertures.

3. A tube holder for supporting one end of a plurality of lamp tubes in side by side relationship comprising a plate formed of insulating material and having a series of apertures disposed in side by side relationship for receiving the terminals of said tubes, a plurality of substantially flat resilient contact strips spaced from each other and disposed in a plane parallel to the plane of said plate and anchored to said plate and arranged so that each aperture will be partially covered by the end portions of two of said contact strips, said two end portions being laterally spaced from each other whereby each tube terminal will be engaged by two of said resilient contact strips, certain ofsaid resilient contact strips being so positioned as to partially cover adjacent openings and being anchored at their intermediate portions, and two of said resilient contact strips which partially cover the end apertures of said series being provided with terminals whereby a series connection will be established through said resilient contact strips and through the tube terminals when a tube is received in each of said apertures.

4. A tube holder for supporting one end of a series of lamp tubes in side by side relationship comprising a tube supporting member formed of insulating material and having a plurality of apertures for receiving the terminals of said tubes, and a plurality of terminal engaging elements arranged in pairs which are spaced from each other and resiliently mounted on said tube supporting member behind said apertures whereby each tube terminal will be engaged by two of said elements which are spaced from each other, one element of each pair being in direct electrical connection with one element of an adjacent pair, whereby a series connection will be established through said spaced terminal engaging elements and through the tube terminals when all the tubes of said series are received in said apertures, said terminal engaging elements being in the form of substantially fiat leaf springs which are disposed in a plane parallel to the rear surface of said tube supporting member, the free end portions of said leaf springs being adapted to be displaced rearwardly when engaged by a tube terminal.

5. A tube holder for supporting one end of a series of lamp tubes in side by side relationship comprising a plate formed of insulating material and having a series of apertures disposed in side by siderelationship for receiving the terminals of said tubes, and a plurality of substantially flat resilient contact strips spaced from each other and disposed in a plane parallel to the plane of said plate and anchored to said plate and arranged so that each tube terminal will be engaged by two of said spaced resilient contact strips, all but two of said resilient contact strips being so positioned as to be engaged by the terminals of adjacent tubes and being anchored at their intermediate portions, and the remain- .7 Y ngziwm Qzf:Sairrlent-contact stzpgengagmg STATES pAENTS the; 12er11r1-i1r1a1s of.. the end; tubes; of said` series Number Name Date whereby* l: Sries connection will be 5111111511111 1689485 Hendry. Oct. 30. 1928 through saidspacedkreslient Contact strips and 2 025-471 OsborneL Dec 24 1935 through thetube terminals when' al1 the tubes of 5 2269978, Kronmml: Jan; 13, 1942 said'fselfiesarefreoevedn saidaper-tulfes. 2f274682 Ford `l Man 3' 1942 EDWIN G- GODDA'RD- 2,295,757 Russen sept. 15, 1942 2,298,935 Freeman Oct. 13; 1942 2,401,555 De Reamer JuneA, 1946 REFERENCES CHE 10 2,447,365. Ruesch Aug. 17, 1948 Thefollowing references are,Y of record in the 2,449,450 Carlson Sept. 14, 1948 me of this patent: 2,464,643 Kuma,V Mar; 15)Y 1949 

